Simultaneous optimization of ultrasound-assisted extraction of flavonoid compounds and antiradical activity from Artemisia herba-Alba using response surface methodology.

Artemisia herba-alba (Aha) is an aromatic and medicinal plant rich in health-promoting flavonoids compounds that play an important role as antioxidant. For better utilization of this resource, the ultrasound-assisted extraction (UAE) of flavonoids and antiradical activities of obtained extracts from Aha using response surface methodology was assessed. A four-factor five-level central composite rotatable design was employed to discuss these extracting parameters: ethanol concentration (X1), temperature (X2), extraction time (X3) and solvent to sample ratio (X4). The optimum extraction conditions for simultaneous maximization of total flavonoids (TF) and scavenging activity were solvent concentration of 50%, temperature of 55 °C, extraction time of 50 min and solvent to sample ratio of 90 mL/g. Under these conditions, the experimental yield of TF and DPPH-radical scavenging activity IC50% were respectively 102.49 mg CE/g DM and 7 µg/mL. Additionally, good and moderate linear correlation was observed between antiradical activity and TF content (R2 = 0.709) which indicated that these compounds are responsible for antioxidant activity of Aha. When compared to the most conventional extraction, antioxidant activity and amounts of major flavonoids are enhanced when using UAE with reduced extraction time.

Development of catechin-phospholipid complex to enhance the bioavailability and modulatory potential against cadmium-induced oxidative stress in rats liver.

The natural flavonoid (catechin) has been shown to possess a multitude of pharmacological activities. However, oral administrated catechin (CT) failed to fulfil its therapeutic potential due to poor absorption and low bioavailability. Thus, is a pressing need to develop a new approach from to increase its intestinal absorption and improved bioavailability. In this work, we intended the increase the bioavailability of CT by preparing catechin-phospholipid complex (CT-PH) and evaluate the protective effect of CT-PH complex against cadmium caused liver injuries in rats. Oral bioavailability of CT and CT-PH complex was evaluated in rats and the plasma CT was estimated by HPLC analysis. The greater absorption of CT-PH complex rats indicated that improved bioavailability. Liver function markers, lipid peroxidation, protein oxidation, antioxidant status and histopathological changes were determined in normal and treated rats. Moreover, biochemical analysis and histopathological examinations indicated that CT-PH provided better protection to rat liver than free CT.

Phenolic compounds analysis, antioxidant, and hepatoprotective effects of Periploca angustifolia extract on cadmium-induced oxidative damage in HepG2 cell line and rats.

A total of five components (Catechin, Caffeic acid, Ferulic acid, Rosmarinic acid, and Amentoflavone) were identified in Periploca angustifolia leaf methanolic extract. This extract did not cause any cytotoxic effect on HepG2 cell line within the range of concentrations tested (0-400 µg mL-1). Thus, pre-treatment with 100 µg mL-1 of P. angustifolia leaf methanolic extract (PAE) significantly (p < .05) protective HepG2 cells against cytotoxicity induced by cadmium exposure. However, Cd-intoxication significantly (p < .05) increased alanine and aspartate amino transferases serum activities (ALT and AST) and bilirubin content by 1.85-, 1.13-, and 3.55-fold, respectively. The levels of hepatic antioxidant parameters including superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) were significantly (p < .05) decreased in Cd-intoxicated rats with concomitant enhancement of lipid peroxidation. Our results showed that P. angustifolia leaf methanolic extract can induce antioxidant effects and also exerts beneficial effects for the treatment of Cd-induced hepatotoxicity.

Microwave-assisted extraction and pharmacological evaluation of polysaccharides from Posidonia oceanica.

Microwave-assisted extraction was employed for the isolation of polysaccharides from Posidonia oceanica (PPO). The extracting parameters were optimized adopting response surface methodology. The highest polysaccharide yield (2.55 ± 0.09%), which is in concordance with the predicted value (2.76%), was obtained under the following conditions: extraction time 60 s, liquid-solid ratio of 50:1 (mL/g) and power of 800 W. This polysaccharide, with molecular weight of 524 KDa, characterized by gas chromatography-mass spectrometry showed that PPO was mainly composed of galactose, glucose, and arabinose with molar percentages 25.38, 24.37, and 21.64%, respectively. The pharmacological evaluation of PPO using animal models at the dose of 100 mg/kg indicated a significant anti-inflammatory activity with a percentage of inhibition of edema of 54.65% and a significant antinociceptive activity with 78.91% inhibition of writhing for peripheral analgesic activity and an increase in the hot plate reaction time for central analgesic activity.

Optimization extraction of polysaccharide from Tunisian Zizyphus lotus fruit by response surface methodology: Composition and antioxidant activity.

Response surface methodology using a Box-Behnken design was employed to optimize extraction temperature, extraction time and ratio of water to material to obtain a maximum polysaccharide yield with high uronic acid content and antioxidant property from edible Zizyphus lotus fruit. The optimal conditions were: extraction time of 3h 15min, extraction temperature of 91.2°C and water to solid ratio of 39mL/g. Under these conditions, the experimental extraction yield, uronic acid content and 2,2-diphenyl-1-picrylhydrazyl scavenging ability (IC50) were 18.88%, 41.89 and 0.518mg/mL, respectively. Chemical analysis revealed that the extract was composed of 97.92% carbohydrate of which 41.89% is uronic acid. The extracted polysaccharides, with an average molecular weight of 2720kDa, are composed of arabinose, rhamnose, glucose, fructose, galactose and xylose. Moreover, the polysaccharides exhibited a significant reducing power and anti-lipid peroxidation activities.